Sound-box for sound recording and reproducing machines



I. F. BURTON.

SOUND BOX FOR SOUND RECORDIN NAND REPRODUCING MACHINES.

- APPLICATION FILED maze, 191s. RENEWED JAN. 17,1920.

1,350,590, Patented Aug- 24,1920.

HHHIIHII U/HTII I d2 Egg 4 9 j 11 56 j; 5/ 36 3g 14 14E] 3. 3 10 7' 36,r zfi-z 681625 4 C f J M4 I J 737 l 27 AOJ INVENTOR ATTORNEYS UNITEDSTATE PATENT OFFICE.

ISAAC F. BURTON, OF PIIILADELPHIA, PENNSYLV ANIM, ASSIGNOB TO VICTORTALKING MACHINE OOIVIPANYYA CORPORATION OF NEW JERSEY.

. SOUND-BOX FOR) SOUND RECORDING AND REPBODUCING- MACHINES.

Specification of Letters Patent. Patented A11g.'2-:l, 1920.

Application filed April 28. 1916, Serial No. 94,118. Renewed January17., 1920. Serial No. 352,230.

'1 '0 all whom it may concern: f

Be it known that I, IsAAo F. BURTON, a citizen of the United States, anda resident of the city of Philadelphia, county of Philadelphia, andState of Pennsylvania, have invented certain new and useful Improvementsin Sound-Boxes for Sound Recording and Reproducing Machines, of whichthe following is a specification.

My invention relates particularly to the providing of means forpositively varying and fixing when varied, the pitch or note of adiaphragm when mounted in, a sound box for sound reproducing apparatusand particularly in such sound boxes where the inherent resiliency ofthe diaphragm is relied upon to control the action of the stylus bar ofthe sound box as modified and assist ed by the coiiperative control andadjust ment of a coacting spring member.

In such sound boxes it is an object of my invention to provide a readyadjustm t of the spring member which may be positively fixed in positionafter the necessary or desired relation and'adjustments of the springcontrol to the diaphragmhave been asceritained and imparted to thespring memaer.

While it is old to extend the action of a spring controlled to thediaphragm even to the extent of producing a very material depression ofthe surface of the diaphragm when not in use, my invention differs fromsuch old construction inasmuch as it is a purpose of my invention toprovide means adapted not only to depress the surface of the diaphragm adefinite amount if the same is desirable or necessary, but, on the otherhand, to make the outer surface of the diaphragm'convex rather thanconcave when that condition is requisite to produce the best results.Not only do I contemplate and v provide for the distortion of thesurfaceof the diaphragm to render its outer surface convex or concave, but Iprovide for an exact, definite adjustment of the diaphragm either wayfrom convexity to concavity and therebetween and when so adjusted in adefinite position, I place the diaphragm and stylus bar under a tensionsuited to the particular characteristic of the diaphragm. For the mostpart, commercial diaphragms for the use specified are out out of micewith the minimum tendency to fracture and split into numerous layers.The diaphragms as applied to a sound box are those of a certaindiameter. and thickness and each one when mounted in a sound box has acharacteristic response or note upon being suddenly struck, so that tothe ear of one skilled in adjusting sound boxes the sort of adjustmentrequired by the'particular diaphragm becomes at once apparent. If thenote given. off is flat a rise in pitch is necessary and the amount,approximately, is apparent to the inspector, while in case the note ofthe diaphragm is sharp a lowering in pitch is required, and by means ofmy invention, an inspector may vary the spring influence upon thediaphragm to raise or lower the note of the diaphragm to such an extentas shall make the note correct.

To meet the conditions above described, I have devised means the objectof which is to positivelyvary and fix the pitch or note or a diaphragmdepending upon the characteristic of eachdiaphragm as installed in asound box and thereafter to fixedly lock the adjustment means. Such anoperation is not the same, manifestly, as that formerly used when thediaphragm is arbitrarily depressed and held there merely to tension thediaphragm without regard to the par ticular kind of'positioning bestadapted to each diaphragm.

In the drawing accompanying this specification and relating thereto,Figure 1. shows a side view, partly broken away, of a sound box to whichI have applied my improvements; Fig. 2 shows a front elevation of thesound box; Fig. 3 shows an enlarged bottom plan view of the sound box;Fig. 4 is an enlarged rear elevation of the sound box showing themounting and adjacent parts; Fig. 5 shows in detail the mounting byitself; Fig. 6 shows a side view of mounting shown in Fig. 5. i

The sound box casing 1 of well known construction has at its back theconnecting member 2 and within its body proper thediaphragm 3 to whichis attached the upper end of the stylus bar 4:. At its lower end thestylus bar is provided with the usual socket to receive the needle 5,which is fastened therein by the thumb screw 20.

Above the lower end of the stylus bar are formed two shoulders 18,between which the resilient ring stylus bar mounting 9 is tightlyfitted, a set screw 19 in aperture 12 serves to securely fasten the ring9 to the stylus bar. The resilient ring member 9 is clearly shown byitself in Figs. 5 and :6. The aperture 12 is positioned on the diameterof the ring member, circular for the most part, at right angles to thatdiameter extending through the center of the apertures ll, 11, whichwith an antii'riction member therein form the axis upon which the stylusbar oscillates under the influence of a needle in contact with a soundrecord of commercial form, which action is Well known.

Somewhat more than half of the ring member 9'is of circular shape on theexterior, and interiorly the circle is complete. The remainder ;of themember 9 is much reduced in cross section with an incident flatteningout of the material, and as flattened, the material is formed into twowings 1.0, 10 extending outwardly radially from the center or body ofthe ring which are provided with apertures 23 therein, Referring to Fig.(3, it will be noted that in addition to being flattened a portion ofthe ring member 9 is formed. with two bends, one, 24, torming a shoulderand the other, 25, bringing the wings 10 into a plane parallel with theHat sides of the member 9. The member 9 when formed is hardened andtempered as a spring; thus the reduced portion becomes a flat springmember and the entiremember 9 becomes substantially a r.e silient springring. A. portion of the lower part of the sound box casing l, is removedand on the that portion thus formed is tastened a plate 7, by means ofscrews 8 or other well known means in such manner as to con ipletelyavoid any loosening, The plate 7 has two lugs 6, (S, which partly.encircle the ring member 9. Near the outer ends of the lugs 3,twogdrilled and tapped holes are positioned exactly in line to receivethe machine screws 15 which are provided with lock nuts 1-6. At theinner end of the screws 15 a tapered portion is formed which at the veryend bears a cupped portion suitably formed to contact with small Jhardened steel balls 22, on each side of ,9

and seated in the recesses 11. As the re.- cesses 11 and the screws 15are carefully located in alinement, the arrangement of parts is suchthat a true axis upon which the stylus bar may move is there assembledand formed.

lVhen the resilient spring member 9 is positioned upon the axis of thescrews 15 with the balls 22 in place, the screws 15 are .each moved toexert a slight but definite amount of compression upon 9 and its parts,and the lock nuts 16 are firmly screwed against member '6. Thecompression of the spring member 9 by the screws 15 is such that underno circumstances can independent vibration be induced in the connectedparts of the bearing between the ring 9 and the screws 15. At the sametime, the bearing upon'the balls permits ready vibratory movement ot'the ring 9 upon its axis.

As pressure is applied to the ring 9 in order to tension the same and tohold the stylus bar at connected thereto on its axis without rattling orloosencss of parts, the ring 9 is slightly compressed and tends toassume a slightly elliptical shape. As the pressure is increased, thethinned portion of the ring-like. member may slightly bend transverselybetween the extensions .or wings 10, particularly as the wings orextensions 10 are flexed in opposite directions in applying tension tothe stylus bar as will be referred to below.

After having been so mounted upon the studs or screws 15, thethinresilient wings or extensions 10 are firmly clamped between the nuts 14and 26 on the two studs 21. The studs 21 are also provided with locknuts 27 by means of which they are held in place when finally adjusted.

After the ring 9 has been mounted in the manner above referred to uponthe studs 15-l5, and with the thinned wings or spring extensions 10firmly secured to the studs 21 and the diaphragm being connected to thestylus bar, the tension under which the diaphragm is placed may beascertained by giving a light blow to the end of the stylus bar, and, itthe characteristic tone of the diaphragm is not correct, the tension onthe diaphragm may be adjusted by loosening the nuts 14 and 26 of onewing and applying more or less vertical pressure thereto by adjustingthe nuts upon the stud 21. Tile adjustment of one wing or resilientextension may be sutlicient to bring the diaphragm to the right pitch,but further adjustment is required, the other wing or extension 10 maybe similarly adjusted in the opposite direction. In the above manner thediaphragm may be properly tensioned as desired, and, after it has beenso adjusted or tensioned, the parts may be securely held insuch adjustedposition without any loose ness between the parts It will also be seenthat in adjusting the thin spring extensions or wings 10 in .op positedirections, there may be ,a slight tend- .ency to buckle or bend thethinned portion of the resilient spring ring member 9 be tween the saidextensions 10, but such bending or buckling is at most very slight, ifperceptible at all.

In this ,manner the stylus h r is securely mounted on the sound boxcasing and the ring-like member 9 provides a unitary structure wherebythe stylus bar is yieldingly held tightly on its pivotal mounti 1g tooscillate in accordance with sound vibrations and whereby the necessaryor desired tension may be applied to the diaphragm to bring it to itsproper or desired pitch.

The foregoing adjustments clearly serve to position the diaphragm and asthe web 13 is of reduced form, it possesses considerable spring actionwhich cooperates with the resiliency of the diaphragm to influence themotion of the stylus bar.

Having thus fully described my invention, I claim and desire to protectby Letters Pat ent of the United States:

1, In a sound box for sound reproducing machines, the combination of asound box casing, a diaphragm mounted therein, a stylus bar, a resilientring forming a mounting for and surrounding said stylus bar, said ringbeing provided with a thin resilient extension projecting therefrom andintegral therewith, means to pivotally mount said ring on said casingand to subject said ring to transverse compression, and a means engagingsaid extension at spaced points respectively to flex said extension inopposite directions.

2. In a sound box for sound reproducing machines, the combination of asound box casing, a diaphragm mounted therein, a stylus bar, a resilientring forming a mounting for and surrounding said stylus bar, said ringbeing provided with a pair of thin resilient extensions projectingoutwardly from one side thereof and integral therewith, means topivotally mount said ring on said casing and to subject said ring totransverse compression and means to apply pressure to said extensions toflex the same in opposite directions.

3. In a sound box for sound reproducing machines, the combination of asound box casing, a diaphragm, a stylus bar, an annular mounting forsaid stylus bar through the opening of which said stylus bar extends,means mounted on said casing to support and diametrically compress saidannular mounting, said annular mounting being provided with an integralresilient portion extending outwardly from said mounting between saidmeans mounted on said casing and in a plane substantially normal to theaxis of said annular mounting, and means for flexing said resilientportion in opposite directions and substantially parallel to the axis ofsaid member to tension said stylus bar and said diaphragm.

4. In a sound box for sound reproducing machines, the combination of asound box casing, a diaphragm mounted therein, a stylus bar, a resilientring providing a mounting for and surrounding said stylus bar andprovided with a thin resilient portion extending outwardly from the bodyof said ring, means to pivotally mount said ring on said casing, and apair of adjusting screws engaging said resilient portion and opera tiveto flex said portion in opposite directions to apply tension to saidstylus bar and said diaphragm.

5. In a sound box for sound reproducing machines, the combination of asound box casing, a stylus bar, a substantially annular mounting forsaid stylus bar, means mounted on said casing to pivotally support anddiametrically compress said mounting, said mounting being provided witha pair of thin resilient extensions projecting radially from the bodyportion of said mounting, and on one side of a line passing through thepivotal axis of said ring, and adjustable means to flex said extensionsin opposite directions at substantially right angles to the normalsurfaces of said extensions.

6. A mounting for a stylus bar of a sound reproducin machine, comprisinga resilient ring adapted to be attached'to and surround a stylus bar andprovided with a pair of diametrically oppositely positioned recesses,and with a plurality of thin resilient projections extendingsubstantially radially from the same side of said ring between saidrecesses and adapted to be flexed in opposite directions.

7. In a sound box for sound reproducing machines, a sound box casing, adiaphragm mounted therein, a stylus bar, a substantially annularmounting for said stylus bar, means mounted on said casing to pivotallysupport and diametrically comoress said mountin

